Carrier for pneumatic tube conveyors



April 26, 1960 H. A. NIEHAUS CARRIER FOR PNEUMATIC TUBE CONVEYORS MENTOR. MFA/W4. lV/El/IMS BY M W Filed March 24, 1959 Fig. 4

by a detachable cover plate.

United States Patent CARRIER FOR PNEUMATIC TUBE CONVEYORS Henry A. Niehaus, West Mifflin, Pa.

Application March 24, 1959, Serial No. 801,548

8 Claims. (Cl. 243-34) This invention relates to pneumatic tubular conveyors of the type used in steel mills for the transport of metal specimens to the chemical laboratory for metallurgical analysis. More particularly it relates to a carrier of improved construction for use in conveyors of the character indicated.

In the steel industry pneumatic conveyors are commonly employed to send metal specimens from the open hearth, pouring ladle, and other points in a mill to a chemical laboratory for analysis and, since the specimens to be handled usually weigh about two pounds, special carriers of rugged construction are required. One common form comprises a steel cylinder in which the specimens to be carried are received and which has closure caps threaded on the ends thereof, so that they may be removed for the insertion and removal of the specimens, the caps being provided with the usual graphite impregnated bumper caps and air seals required for movement of the carrier through the conveyor tube. In operation, stoppages in the conveyor tube have occurred as the result of the end caps, particularly the one at the trailing end of the carrier, becoming disengaged in transit, and this requires both location and removal of the stoppage to restore the conveyor to working order. This is a particularly trouhlesorne operation in conveyors that extend over a distance of a mile or more, and outage times of twenty-four hours are frequently required for pipe-fitters to locate the point of stoppage and restore the system to working condition. During outage times of this character, the specimens must be delivered to the chemical laboratory by surface conveyors and longer periods of time are required in order to obtain a metallurgical analysis thereof.

One of the objects of this invention is to provide a carrier of improved construction that is not subject to disassembly during transit through a pneumatic conveyor tube and which will not cause stoppages therein of the character mentioned above. To this end, the invention contemplates a carrier in the form of a steel cylinder that has closure caps permanently attached to the ends thereof and in which access to the interior of the steel cylinder is provided through a side opening that is normally closed In a manner to be described the cover plate is detachably attached to the carrier by a fastening connection that effectively prevents its removal during transit. In a manner to be further described, the mounting of the cover plate provides for its removal and replacement only by reverse movements thereof in two opposite axial directions to and from an operative covering position, and a manually releasable and automatically engageable detent is provided for preventing its movement out of its operative covering position.

Other objects and advantages of the invention will become apparent from the following description and accompanying drawings, in which:

Figures 1 and 2 are isometric views respectively of the carrier and cover plate of this invention;

'ice

Figure 3 is a sectional view taken substantially in the plane of the line III-III of Figure 1 which shows the cover plate in a partially assembled position on the carrier; and

Figure 4 is a fragmentary sectional view similar to Figure 3, but showing the cover plate in fully assembled position.

The carrier of this invention, as best shown in Figures 1 and 2 of the drawings, comprises a steel tube or cylinder 1 which has a segmental portion 2 removed therefrom to form a side opening 3 providing access to the interior thereof. In a manner to be described, the segmental portion 2 forms a detachable closure cover plate for the opening 3.

Opposite ends of the tube 1 are sealed by caps 4 and 5 which are permanently attached thereto and form end closures therefor. The caps 4 and 5 are circular steel plates and are provided respectively with inwardly facing annular grooves or slots 6 in which the ends of the cylinder 1 are received and permanently secured as by welding. The arcuate portions 7 and 8 of the annular grooves 6, which are respectively arranged in facing portions 9 and 10 of the caps 4 and 5 at opposite ends of the opening 3, act as keeper or anchor slots for the cover 2 in a manner to be described. Graphite impregnated felt bumper pads 11 and fabric disks 12 are secured to the outer ends of the caps 4 and 5 by bolt and washer assemblies 13. The peripheries of the fabric disks 12 are adapted to have air sealing engagement with the internal surface of a pneumatic conveyor tube (not shown) through which the carrier is forced by compressed air, and the pads 12 provide lubrication for such movement and absorb shock in the customary manner of such elements.

The cover 2 is shortened so that it has a length between its opposite ends 14 and 15 that is slightly less than the axial length of the cylinder 1, but greater than the facing surfaces 16 and 17 on the portions 9 and 10 at the outer ends of the keeper slots '7 and 8. In this manner, the slots 7 and 8 provide for axial movement of the cover 2 when it is in its assembled position covering the opening 3 as best shown in Figure 4. In order to provide for removal and replacement of the cover 2, its axial length between the ends 14 and 15, more particularly, is slightly less than the distance between the surface 16 on the end cap 4 and the bottom or inner surface 18 of the keeper slot 8 to thereby provide for its axial movement to a detachable position in which its end 15 is bottomed in the keeper slot 8 and its opposite end 14 is clear of the keeper slot 7. When moved to this position, the cover 2 may be tilted as shown in Figure 3 and withdrawn from the keeper slot 8. In order to provide for this tilting movement, the radial inner surface 19 of the keeper slot 8 is enlarged or undercut with a taper as shown in Figure 3 of the drawings. The cover 2 is further provided with two elongated slots 24 that act as finger grips to facilitate its removal and replacement with respect to the access opening 3.

A manually releasable lock is provided for preventing accidental dislodgment of the cover 2 from a closed position. As best shown in Figure 3, it comprises a detent rod 21 mounted for axial movement in a bore 22 extending radially of the cap 4. The bore 22 is enlarged at one end 23 thereof in which an enlarged head 24 on the inner end of the rod 21 is received. A spring 25 is arranged in the enlarged bore 23 with one end bearing against the rod head 24 and its other end bearing against cap screws 26 threaded therein. The spring 25 provides a bias for moving the detent rod 21 radially outwardly to the position shown in Figures 3 and 4 in which its head 24 abuts against the inner end of the bore enlargement 23. The outer end 27 of the detent rod 21 engages in an opening 28 which is arranged in the cover 2 at a point spaced inwardly from its end 14. When the end 27 engages in the opening 28 as shown in Figure 4, endwise movement of the cover 2 is prevented and thereby its disengagement with respect to the keeper slots 7 and 8.

In operation, the cover 2 is assembled on the carrier by placing it in the tilted position shown in Figure 3 with its end 15 bottomed in the keeper slot 8. Its other end 14 is then lowered to a position in which it depresses the detent 27 in the bore 22 against the action of the biasing spring 25 so that the cover 2 may be moved axially to the left and to the position in Figure 4 in which both of its ends 14 and 15 are received in the keeper slots 7 and 8. Upon movement to this position, the detent 27 moves upwardly under the action of its biasing spring 25 and engages in the cover opening 28 to thereby lock the cover 2 against axial movement in the keeper slots 7 and 8. The cover 2 is thus securely held in closed position over the access opening 3 so that it can be removed only by first depressing the detent 27 to a position in which it clears the opening 28 to enable movement of the cover 2 to the right as viewed in Figures 3 and 4. The cover 2 may then be tilted to the position shown in Figure 3 so that it may be removed from the keeper slot 8.

The cylinder 1 is preferably provided with a plurality of drilled openings 29 in opposite sides thereof to provide for manipulation of the carrier by handling hooks.

From the foregoing it will be apparent that the carrier of this invention is constructed in such manner that stoppages in a pneumatic conveyor tube as the result of accidental disassembly of its parts during transit are effectively prevented. In this respect, attention is particularly directed to the fact that its end caps 4 and are permanently attached to the cylinder 1 and the detachable mounting of the cover 2 in the keeper slots 7 and 8 prevents its accidental dislodgment during movement of the carrier through a conveyor tube.

While one embodiment of my invention has been shown and described it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. A carrier for pneumatic conveyors comprising a cylindrical shell having a segmental portion removed therefrom to form an opening providing access to the interior thereof, a pair of cap-plates secured to and forming closures for opposite ends of said shell, said cap-plates having facing portions with arcuate slots therein respectively arranged at the ends of said shell opening, a detachable cover comprising the said segmental portion normally supported in a covering position over said opening with opposite ends thereof received in said slots, said cover being movable in an axial direction in said slots and having a length greater than the spacing between said facing portions but less than the distance between one of said portions and the base of the slot in the other of said portions to provide for movement of said cover to a detachable position in which one of its ends is clear of the slot in said one portion so that it may be removed from its covering position, and means including a manually releasable detent for holding said cover against axial movement from its said normal covering position with both of its ends received in said slots.

2. A carrier as defined in claim 1 characterized by the slot in said other portion having an under-cut enlargement providing for tilting of said cover when moved to said detachable position so that it may be withdrawn by endwise movement out of said last-named slot.

3. A carrier for pneumatic conveyors comprising a tubular body with a side opening therein providing access to its interior, a pair of anchoring members secured to said body at opposite sides of said opening and respectively having portions in facing relation with anchoring slots formed therein, a detachable cover arranged over said opening with opposite edges thereof received in said slots, said slots providing for movement of said cover in a direction transversely of said members to a position in which one of its said edges is clear of one of said slots to enable removal of said cover from said body, and means including a manually releasable detent for engaging and .holding said cover against movement to said position.

4. A carrier as defined in claim 3 characterized by said cover having a dimension between its said opposite edges which is greater than the spacing between said facing portions but les than the distance between one of said members and the base of the slot in the other of said members.

5. A carrier as defined in claim 3 characterized by said detent being movable into operative holding engagement with said cover when it is returned to a covering position with both of said opposite edges received in said slots.

6. A carrier as defined in claim 5 characterized by said cover having an opening spaced inwardly from one of its said edges in which said detent has a snug fit and is received upon movement of said cover to said covering position.

7. A carrier as defined in claim 6 characterized further by said detent comprising a rod mounted for endwise movement in a direction radially of said body, and spring means biasing its movement to a position in which it en gages in said cover opening.

8. A carrier for pneumatic conveyors comprising a cylindrical shell having a segmental portion removed therefrom to form an opening providing access to the interior thereof, a pair of cap-plates secured to and forming closures for opposite ends of said shell, said cap-plates having facing portions with arcuate slots therein respectively arranged at opposite ends of said shell opening, a detachable cover comprising the said segmental portion normally supported in a covering position over said opening with opposite ends thereof received in said slots, said cover being movable in an axial direction in said slots and having a length greater than the spacing between said facing portions but less than the distance between one of said portions and the base of the slot in the other of said portions to provide for its movement to a detachable position in which one of its ends is clear of the slot in said one portion so that it may be removed from its said covering position, said cover having a locking opening spaced inwardly from its said one end, a detent comprising a rod mounted for movement radially of one of said caps and adapted to engage in said locking opening when said cover is moved to its said normal covering position, and a spring biasing the movement of said detent rod to an engaged position in said locking opening, said detent rod being manually movable against the action of said biasing spring to a position in which it clears said locking opening to enable movement of said cover to its said detachable position.

References Cited in the file of this patent UNITED STATES PATENTS 

